Decellularized Human Lung Scaffolds as Complex Three-Dimensional Tissue Culture Models to Study Functional Behavior of Fibroblasts.

In vitro culturing of cells in two-dimensional (2D) environments is a widespread used methodology in biomedical research. Most commonly, cells are cultured on artificial plastic dish surfaces, which lead to abnormal functional behaviors, as plastic does not reflect the native microenvironment found in vivo or in situ. Therefore, a multitude of three-dimensional (3D) cell culture systems were developed in the past years, which aim to bridge the gap between 2D cell culture dishes and the in vivo situation. One of the more recent development in the field, the generation of viable precision-cut tissue slices from various organs emerged as an exciting approach to study complex interactions and biological processes ex vivo in 3D. Decellularization of such tissue slices leads to the removal of all functional cells, and leaves behind a scaffold of extracellular matrix (ECM), which closely recapitulates the molecular composition, mechanical properties, topology, and microarchitecture of native ECM. Subsequently, decellularized precision-cut lung slices (PCLS), also called 3D lung tissue culture (3D-LTCs), can be successfully reseeded with a variety of cell types, including fibroblasts, which attach to and engraft into the matrix. Here, we describe the generation of PCLS from resected human lung tissue and their decellularization and recellularization with primary human fibroblasts. This novel 3D tissue culture model allows for various functional studies of fibroblast behavior on native ECM composition and topology.